850 Gear Down ?

FatDogX · Dec 16, 2018

I did a little searching but not a lot of info yet, so I thought I would start a thread on gearing down or just general gearing changes on the the 850.

First, anyone try the Pro gears (gear down) on the new 850? I know this was / is popular with the 800, in fact I did this upgrade on my 2017 and had good luck with it.

Second, anyone upgrade to the Kurt's gear down or the TKI set up? If you are running the TKI, what gears did you go with and what was the outcome ?

Anyways, just looking for some thoughts and feedback.

Nitroused383 · Dec 17, 2018

My dad and brother both have 163 2.6 850's. My brother has installed the pro gears on his sled but my dad hasn't installed his yet. So far we've only gone on a couple road rides for break in. I've ridden both back to back and on the trail there isn't much difference. Stock gears feel a little more grunty where the pro gears feel a little more zingy? Both sleds only have about 5 hours and we are hoping for some better snow this weekend to check clutch / belt temps between the 2 sleds. I will keep you updated but the pro gears are a great budget gear down as you know. Oh and one other comparison is the sway bar unhooked on one and not the other. No sway bar dives pretty bad with the narrow front end. You will want to tighten the springs if you do that.

FatDogX · Dec 17, 2018

Great info, definitely keep us updated as you guys have an awesome side by side comparison!!!

Nitroused383 said:
My dad and brother both have 163 2.6 850's. My brother has installed the pro gears on his sled but my dad hasn't installed his yet. So far we've only gone on a couple road rides for break in. I've ridden both back to back and on the trail there isn't much difference. Stock gears feel a little more grunty where the pro gears feel a little more zingy? Both sleds only have about 5 hours and we are hoping for some better snow this weekend to check clutch / belt temps between the 2 sleds. I will keep you updated but the pro gears are a great budget gear down as you know. Oh and one other comparison is the sway bar unhooked on one and not the other. No sway bar dives pretty bad with the narrow front end. You will want to tighten the springs if you do that.

tdbaugha · Dec 17, 2018

Mine is geared down with pro pulleys. There's no downside really, unless you like high speed trail riding.

FatDogX · Dec 17, 2018

tdbaugha said:
Mine is geared down with pro pulleys. There's no downside really, unless you like high speed trail riding.

Kinda what I've been thinking. I have set lying here ready, but figured I would be nice to hear some direct feedback.

d8grandpa · Dec 17, 2018

tdbaugha said:
Mine is geared down with pro pulleys. There's no downside really, unless you like high speed trail riding.

What would be your final gear ratio that you are running.

tdbaugha · Dec 17, 2018

https://www.snowest.com/forum/showthread.php?t=424354&highlight=pro+pulleys

damx · Dec 22, 2018

Any of you guys blow a quick drive belt when using the pro top/bottom gears on you're axys 800/850? Also do you need to add more clutch weight or a bit steeper helix when gearing down ?

2XM3 · Dec 22, 2018

I have it on my 800, imho as the 850 has a bit more stroke you probably would notice less difference, now i'm saying that assuming you would get the clutching spot on. IE with stock gearing in my 800 I ran a different helix than the 40, but after the pro gear swap, the stock 40 I liked better. I think it just has to be a try and see if YOU like the way it feels. super easy to swap back, and cheap to do as well

damx · Dec 22, 2018

On my 850 I'm stock with Indy specialty clutching 10.5 hours ,120 miles. I'm only getting my belt about 1.5" from top of primary. Full shift? Think that's what it's called. My buddies 850 380 miles all stock clutching ( 72g ), with a tki belt drive, has better track speed and belt gets 3/4" to the top of the primary.

Teth-Air · Dec 22, 2018

850 with a 174 and I stayed with stock ratio of 2.3 (or 2.52 equivalent with 8 tooth drivers) but switched to TKI. Rolls much better. This is pretty good gearing but if switching a QD to 2.42:1 is a huge improvement over sky high stock gearing.

cvcustoms · Dec 22, 2018

damx said:
On my 850 I'm stock with Indy specialty clutching 10.5 hours ,120 miles. I'm only getting my belt about 1.5" from top of primary. Full shift? Think that's what it's called. My buddies 850 380 miles all stock clutching ( 72g ), with a tki belt drive, has better track speed and belt gets 3/4" to the top of the primary.

You want to be in the 3/4” range. Are you running patriot weights or v5? What primary spring? Are you running the secondary setup also?

Sent from my iPhone using Tapatalk

ullose272 · Dec 22, 2018

damx said:
Any of you guys blow a quick drive belt when using the pro top/bottom gears on you're axys 800/850? Also do you need to add more clutch weight or a bit steeper helix when gearing down ?

Have probably 1200 miles (2400 total on belt) on my pro gears swap. And still going strong. I had a carls helix (62/42 i think) in for a bit but i like the stock helix better. Ive thought about trying a straight 42 helix but just havent gotten around to it.

Sent from my Pixel 3 using Tapatalk

damx · Dec 22, 2018

Yes the patriot weights with a 110-320 primary spring, Indy mountain 3 helix on the lower angle with a 160/260 secondary spring.

cvcustoms · Dec 23, 2018

damx said:
Yes the patriot weights with a 110-320 primary spring, Indy mountain 3 helix on the lower angle with a 160/260 secondary spring.

Have you tried taking any weight out of the weights? You could also try the factory primary spring.

The gear down is definitely a huge plus on these sleds though.

Sent from my iPhone using Tapatalk

damx · Dec 23, 2018

Yes I taken some weight out, and tryed different placement of the magnets. I'm just going to get the pro gears and give them a try.

Scott · Dec 23, 2018

There was a really good spreadsheet that you could enter data (chaincase top and bottom sprocket, track pitch, # of driver teeth, etc) and it would calculate your top end mph with full clutch shift-out.

I've got it saved somewhere, but it's hard to upload on here anymore.

Does anyone still have that spreadsheet?

Spaarky · Dec 23, 2018

Not spread sheet but website Scoots....

http://www.cmsaracing.com/calc.htm

tdbaugha · Dec 23, 2018

kanedog · Dec 24, 2018

1-1 is the best ratio to run.
The absolute minimum at 1-1 is 78 mph on a Polaris.
On a mountain sled, it would never ever ever ever ever reach 78 mph. Therefore, it would never ever ever run in the most efficient part of the clutch, which is 1-1. In the trees ya might get 30mph ground speed, but prolly not even that.
Gear dat bish down so it runs at 1-1 on a climb. Somebody just try this ffs. I have and it’s like a gdam turbo ffs. My n/a sled will smoke turbos in deep snow. It’s embarrassing for the turbos and I actually feel bad for the money they spend. No joke.
Why is this so hard to understand? Peeps been clutching the same way for 40 years. Times up man. Time to change the way ya think.
Flame away and then let’s meet and I can demonstrate the magic of super low gear ratio. Btw, my gear ratio is a 23/80, 3.48, eight tooth drivers, in a naturally aspirated 174 and I’m going to a 23/82 for a 3.56 this year.
And just for kicks, in deep snow, I will pay you $500 cdn if you can beat me. U pay me in beer if you lose.Start from on the hill pointing uphill. No run at the hill. Best out of five. Hugs for the loser.

850 Gear Down ?

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

#getsomegetthere

Well-known member

Well-known member

#getsomegetthere

Well-known member

Scott Stiegler

Well-known member

Well-known member

Undefeated mountain clutching champ of the world.

Similar threads